Bubbling air through septic tank

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Bubbling air through septic tank fluid to help break down solids and scum?

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Hi all, Im new to this forum and homesteading and I have an idea that I would like to know if it's a good one or just pretty stupid. A bit of background: Im 3/4 of the way through building a off-grid A-Frame home in Alaska about 2 1/2 hours north or Anchorage (any neighbors in here?) and due to the cold climate I've been told the anerobic bacterial action in the tank will be slow so I should build oversize and heat it, which I did. I havent gotten all the plumbing installed yet so the thing is still bone dry. Its a insulated 1200 gallon two-partition concrete tank buried 5 feet below ground, the first partition is 800 gal and the second is 400 gal, both are vented. Embedded in the bottom concrete slab are loops of piping that a heated antifreeze solution can be pumped through to help things along during winter and keep it from freezing, the antifreeze loops also extend along 3 of the 6 drainfield pipes.

Since most of the actual digesting occurs in the drainfield with aerobic bacteria doing the work and septic systems usually fail because solids have gotten into the drainfield pipe due to sludge and scum building up in the tank my idea is this:

Can I pump air into the septic tanks and bubble it up through the sludge and scum to help reduce buildup and do some aerobic digesting in the tank before it goes to the distribution box and to the drainfield? I was thinking of a series of plastic soaker hoses along the bottom of the tanks with a low pressure air pump (large fish tank pump?) pumping air once a day for about an hour or so, kind of like what you see in fish tanks where the air hose goes into a block of porous foam and the air bubbles up in tiny bubbles from it. The projected lifespan of the septic system will probably start getting dicey just when Im getting too old to want to muck about with a failing septic system and I want to extend it for as long as possible. I also thought it was just a neat idea for its own sake but Im no engineer. So is a good idea? Or am I just trying to be too clever....

Thanks Dave

-- Dave Harrison (transmach@hotmail.com), April 23, 2000

Answers

Don't know if this will help or not. Just passing on an idea I've heard before. My grandmother and another woman her age always flushed a cake of yeast down the toilet once a month. They say that it helps break things up and have never had septic problems. Whether it would help where you live may be another matter. Has anyone else heard of this method before and does it really work? Just a thought!

-- Pat (pmikul@pcpros.net), April 23, 2000.

My dad, who presently lives in Tok, and has lived in the interior of Alaska almost all his adult life, says that it's better to use a cesspool instead of trying to keep a drain field working. I don't know if you could get away with that where you are, because codes don't allow for cesspools -- and, of course, you've already got your tank in. A cesspool, the way my dad would build it, is logs cribbed with the spaces between the logs left open for drainage -- really not much more than a large outhouse pit, buried in the ground and with the house drains leading to it. Buried deep enough, I don't think they freeze even where he lives (the coldest part of the state). And, if you could run the graywater into a separate one, it ought to last about forever. Keep it well away from anybody's water supply, though.

-- Kathleen Sanderson (stonycft@worldpath.net), April 23, 2000.

The digesting DOES NOT occur in the leachfield! It happens in the septic tank, where anaerobic friendly little buggies digest the solids. Nothing but leachable liquids should flow into the leachfield. If it is operating properly, you should have no problem. The reason for heating is that the little guys get sluggish if temps drop, although I would guess that freezing would be an extremely rare event. Which brings me to: What do your nearest neighbors say? I mean those with a septic system? I would not try to get too cagey, and I believe you are worrying needlessly. And save your yeast. Won't hurt, but you'd be better off making sourdough. GL!

-- Brad (homefixer@mix-net.net), April 23, 2000.

Brad, the problem with leachfields in Alaska is that they freeze up. Most of Alaska (certainly the parts I'm familiar with) get MUCH colder than southern Maine in the winter, and for a much longer period of time. The area where Dave is building his house isn't quite so cold, but almost. So the tank may be doing what it is supposed to, but ice has clogged the leachfield, so the tank doesn't drain, it backs up, and, well, you can figure out the rest of the story! I wouldn't worry too much about the tank freezing, as long as it is buried deep enough, but leach fields just don't work too well in areas with prolonged sub-zero (WAY sub-zero) temperatures. Unfortunately, if you are building in an area with building codes, you are required to put one in, anyway -- seems like someone would get smart and figure out something that would work. I know my dad has advised some people to go ahead and put in the septic system, to show the inspector, and then when he's gone, put in the cesspool. Only thing is, with a cesspool, you really do have to be careful of the water supply -- they get more water run into them than an outhouse, and so there is more chance of pollution from them.

-- Kathleen Sanderson (stonycft@worldpath.net), April 23, 2000.

I have heard fo people putting horse manure in their tanks to build up heat and speed up the break down Grant

-- Grant Eversoll (thegrange@earthlink.net), April 24, 2000.

Thanks for the answers, The freezing is not a problem according to my neighbors, the heat generated by the bacteria and a good insulating snow cover is usually enough to keep it thawed out, except for a winter 4 years ago where it got really cold but didnt snow for a month or so and a few drainfields in my neck of the woods froze up. The septic systems around here are either the really old cess pits, or relatively new built systems put up in the last 5 years (who would have thunk it, urban sprawl in alaska! :-) ). The question I have is will bubbling air through the sludge and scum help reduce buildup in the tank.

Dave

-- Dave (transmach@hotmail.com), April 24, 2000.

No, bubbling air will not help because bubbling air is an entirely different system - aerobic. Septic tanks are designed to be anerobic. When you add air you are changing the type of bacteria and thus the type of system.

Most publicly owned wastewater treatment plants run as an aerated system. If you really want to understand this, go to your nearest municipal wastewater treatment plant and ask for a tour. They are publicly owned, so they are open to the public. The operator or superintendent ought to be able to explain how his system works and how something like an anerobic lagoon works, which just might help you understand your septic system better.

About twenty years ago, aerated "septic" tanks were being installed in this area as a better thing than the normal anaerobic septic tank. It soon became apparent that they were not better, they needed more maintenance and they were more expensive to run. They are now outlawed in this county because so many failed due to neglect.

Septic means septic - anerobic bacteria. That is how they work - without oxygen. When you add oxygen to the mix, you kill off the anerobic bacteria and the aerobic bacteria live.

So you can have one system or the other, but not both in

-- R. (thor610@yahoo.com), April 24, 2000.

but not both in the same tank.

-- R (thor610@yahoo.com), April 24, 2000.

Thanks!

-- Dave (transmach@hotmail.com), April 24, 2000.

Yeast cakes are good. Although if I got the extra dollar or two I use that RID-X stuff - seems to work good too. Either one, just remember to flush it down at night before you go to bed when the system usage should be at its lowest, so it'll have a chance to work, and not just pass through into the leach field.

-- Eric Stone (ems@nac.net), April 26, 2000.

Dave, Back in 79 I built an underground house in a hill, with a lake behind and the county road in front. With no area for a leach field I installed an air system, factory made, all it was, was an air compressor that cycled 15 minutes each hour and had a dispersion type chamber on the outldet end which I placed one of those 3" chlorine tablets in each month. The claim was that you could drink the outflow, which I didn't believe or try. But the water was clear and oderless, and it discharged into the county owned ditch in front of my house. It was also approved by the powers that be, so I think that you can be successful in your attempts. Good luck. Wayne Roach

-- Wayne Roach (R-WAY@msn.com), September 15, 2000.



-- (stinky@pot.com), July 01, 2001


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